Tensioning device for embroidering-machines.



J. A. GROEBLI.

TENSIONlNG DEVICE FOR EMBROIDERING MACHINESl APPLICATION FILED mnzs. l9l3.

1, 1 37,3 1 1 Patented Apr. 27, 1915.

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J. A. GROEBLI.

TENSIOMNG DEVICE FOR EMBROIDERING MACHINES.

APPLICATION FILED MAY26.19I3.

1,137,31 1 Patented Apr. .27, 1915.

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J. A. GROEBLI.

TENSIONING DEVICE FOR EMBROIDERING MACHINES.

APPLICATION FILED MAY 26. 1913.

1, 1 3'7 ,3 l 1 Patented Apr. 27, 1915.

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. THE NORRIS PETERS Co PHOTOVLITHUV, WASHINGTON, .DV 6.

J. A. GROEBLI.

TENSIONING DEVICE FOR EMBROIDERING MACHINES.

APPLICATION FILED MAY 26, 1913.

Patented Apr. 27, 1915.

4 SHEETS-SHEET 4.

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Wzinesses:

THE NORRIS PETERS covv PHOTOVLITHOH WASHINGTON, u c

"UNITED STATES PATENT OFFICE.

JOSEPH A. GROEBLI, OF NEW YORK, N. Y.

TENSIONING DEVICE FOR EMBROIDERING-MACHINES.

Application filed May 26, 1913.

To all whom it may concern:

Be it known that I, JOSEPH A. GROEBLI, a citizen of the United States, and a resident of the city, county, and State of New York, have invented certain new and useful Improvements in Tensioning Devices for Embroidering-Machines, of which the following is a specification.

My invention relates to embroidering niachines, of the class described in my application for Letters Patent of the United States, Serial No. 638,008, filed July 11, 1911., and in which the fabric to be embroidered is so carried upon a movable tambour frame that, when it is desired to present new portions of the fabric to the thread applying needles, it is slackened, fed forward and then stretched taut, longitudinally and transversely. And my improvements are particularly directed to the means whereby the transverse stress is applied to the fabric in such a way as to automatically subject it to a. uniform tension, avoiding both undue stress and insuliicient tension in any portion of the fabric, all as illustrated in the drawings and as hereinafter pointed out and claimed.

In the drawings, in all the figures of which corresponding numerals designate similar parts, Figure 1 is a back View of a tambour frame embodying my invention, the frame, the width of which in practice is usually several times its height, being shortened in the figure by the excision of medial portions. In this figure the tambour frame is shown as being provided with two pairs of fabric carrying rollers; and one of the roller actuating worms is partially broken away to show its cooperating worm gear. Fig. 2 is also a back view, on an enlarged scale of the side tension mechanism for engaging one edge of the upper piece of fabric; Fig. 3 is a top view of the frictionally-actuated connecting mechanism between the pin roller and the cooperating friction roller; Fig. 4 is a cross sectional view, on the line 1, 1 of Fig. 2, showing the side tension grip opened; Fig. 5 is a similar view, showing the side tension grip closed; and Fig. 6 is a plan view on an enlarged scale of one of the plates for carrying the friction rollers of the grip; Figs. 7 and 8 are respectively a plan view and a side view of a modification of the connecting mechanism for opening and closing the grip; Fig. 9 is an elevation, look- Specification of Letters Patent.

Patented Apr. 27, 1915.

Serial No. 769,783.

ing from the right on Fig. 8, of the bracket carrying the spider-limiting stops; Fig. 10 is a side view of the upper portion of the mechanism shown in Fig. 2, looking from right to left on that figure; Fig. 11 is a cross sectional view, similar to Fig. 4, but showing a modified form of the yieldable presser; Fig. 12 is a back View, of a portion of the side tension mechanism embodying this modification; and Fig. 13 is an end view of one of these modified, yieldable pressers.

As is well understood in the art, the tambour frame 2, should be mounted so as to move vertically and laterally in the same plane, being actuated by mechanism which it is unnecessary to now particularly show or describe. And in suitable bearings in this tambour frame are mounted the fabric carrying rollers, 4, 5, which are actuated through worms (5, 7, engaging with worm gears (5 upon the ends of the rollers, the worms 6, 7 being carried by shafts 8 which are actuated, through worm gears 9 and worms 10 upon a shaft 11, revolved by mechanism not shown. For clcarness I have shown each fabric roller 4 or 5 as geared at one end, only.

Centrally of the frame is disposed the roller truing mechanism, consisting of brackets 11, to hold down the lower fabric rollers, and movable brackets 12 carried by a shaft 13, passing up and threaded through the worm gear 16 which rests upon a bearing on the frame and is driven by a worm, the

shank of which is shown at 17, upon the shaft 18, operated by mechanism not shown. These portions of the mechanism are shown to illustrate the elements of the apparatus by which the fabric is fed forward and is stretched longitudinally, and to thereby assist the mechanic in understanding the application of my present improvements which relate to the side tensioning devices, and which 1 will now explain in detail.

Vertical shafts 19, carry the rollers 20, preferably integral therewith, provided with pins 21 projecting forward in the direction of the engaging rotation of the roller. These pins register between the teeth of a comb 22. and also between the friction rollers 48, so that when the rollers are turned forward the pins will project through the slots in the combs '22, penetrate the fabric 23 and enter the spaces between the friction rollers 48; and, when the movement of the rollers 20 1s reversed, the fabric will be stripped from the pins 21 by the comlos 22 as the pins are drawn back from between the friction rollers and the teeth of the combs.

Worms 24 upon shafts 25 mesh with worm gears 26, shown as having extensions or bosses upon their upper sides and secured to the shafts 19, which pass loosely through the friction disks 30 and also through the disks 2? which latter are keyed to rotate with the shafts 19 but may slide lengthwise thereupon and which are pressed against the disks 30 by the springs 28 compressed below the collars 29 on the shafts 19.

Each friction disk 30 is provided with a forked arm 30 carrying a pin 31, projecting from its lower side and entering between the fingers of the forked arm 32 carried by the shaft 33, which is journaled in bearings on the side of the frame. The upper end of the shaft projects upward between the ends 30 and 30 of the forked arm 30 of the disk 30, so as to limit the rotation of the said disk to an arc corresponding to the opening of the fork. And the shaft 33 is also provided with an arm 34, connected by the pivoted link with an arm 36 secured on a rod 37 which rotates in lugs 38 on the sides of the frame.

The arm 36 is provided with an extension 39, pierced with a hole -10, in which is secured a rod 41, the lower end of which is fastened in an arm 13 secured, like the arm 39. upon the rod 37.

Between the arms 39 and 43 are assembled a series of plates 44, for carrying the friction rollers of the side tension grip.

Each of these plates is provided with a hole 43 through which passes the rod 37, a hole 1 6 larger than the rod 41 which passes loosely through it, and a pin 17 projecting from one side of the plate; and upon a pin near the forward end of each plate is journaled a roller 48.

Between every two plates 14 a flat spring -i9 is secured by one of its ends to the shaft 37 with a set screw 50, its other end bearing against the pin 47, so that normally the plate at will be held, relative to the arm 39, in the position shown in Fig. 4, with the outer (in the drawings the lower) side of the hole 46 engaging with the rod 11. This arrangement permits the plate to be sprung outward, by pressure upon its roller end, until the inner (in the drawings the upper) side of the hole -t6 engages with the rod 41; and to this extent each plate moves independently of the others.

The friction rollers correspond in number to the spaces between the pins 21 which register between the rollers.

In Figs. 11, and 13 I have shown a construction in which the friction rollers are omitted, and the plates 44 are provided with stationary ends or terminal members 44,

each plate still retaining its limited sphere of independent movement. And it will be understood that the number of the pins and of the friction rollers may be varied as the size of the machine and the character of the fabric may render expedient, and that the details of the mechanism whereby a yieldable side tension grip is secured may be modified without departing from the spirit of my invention.

The operation of my device is as follows: The mechanism being in the position shown in Figs. 3 and 4, the edge of the fabric 23, (which we will assume has been reeled forward the desired distance by the rollers l. lies between the pin roller 20 and the friction rollers 48. If power is now applied through the shaft 25, worm 2t, and worm gear 26, the shaft 19 and friction disk 27 may be turned in the direction in which the pins 21 project. As soon as the movement begins. disk 30, under the control of the disk 27 and worm gear 26, will swing its arm 3O around into the reverse of the position shown in Fig. 3; so that the pin 31 will swing the arm 32 around until the lower (in the figure) of the forked arms 30*, 30 strikes against the rod Simultaneously, through the turning of the rod 33 the toggle joint 34, 35 is straightened out and carried to or slightly past its dead center, as shown in Fig. 5, causing the arm 39 to swing the series of plate-carried friction rollers inwardly until they grip the fabric against the pin roller, in which position they will be locked, owing to the toggle joint being on or past its dead center. The disk 30, being arrested by its forked arm engaging the shaft 33, noW allows the worm gear 26 and the disk 27 to slip a ainst it, and the shaft 19 to continue to revolve, causing the roller 20 to draw forward the fabric 23 between itself and the friction rollers 18, but in such a manner that, when the fabric between one of the rollers 48 and part of the roller 20 becomes suliiciently taut, then the roller 20 slips as to that part of the fabric, and consequently th: particular roller 48 ceases to revolve. The pressure, however, between roller 20 and the particular roller -18 is preserved, in order that this particular portion of the fabric shall remain taut; and as the roller 20 continues to revolve, it will draw forward the slacker portions of the fabric until, when the pins 21 enter the fabric, and seize it with a positive grip, all parts of it will have been brought up to an equal tension.

)Vhen it is desired to release the fabric from the lateral tension, the revolution of the shaft 25 is reversed from that above described, which immediately throws the friction disk 30 around into the position shown in Fig. 3, unlocks the toggle joint 31, 35, raises the bank of friction rollers 18,

and, as the shaft 20 continues to revolve, strips the pins 21 out of the fabric.

In describing the foregoing operation I have for clearness spoken of the side tensioning apparatus at one side of one piece of the fabric only. But it will of course be remembered that the duplicate mechanism at the other side of the fabric operates simultaneously but in the reverse direction, and that if two pairs of fabric rollers are being used in the same frame, the operation of the side tensioning apparatus for both pairs will be simultaneous. In this manner I secure a side tensioning device wherein the fabric is first seized with a yielding or slippable grip and stretched by tractors to a substantially uniform tension before being positively held; and in which, also, the yielding grip is at once relaxed when the tension is to be removed, so that the fabric will not be grasped between the friction rollers and the pin roller during the un winding of the fabric from the pin rollers.

The modification shown in Figs. 7 and 8 consists in the substitution, for the frictional disk 30, of a gear wheel positively fastened upon the shaft 19; while instead of the slotted arm 32 I fasten to the shaft 33 a spider 53 carrying a toothed segment 54.

adapted to mesh with the teeth of the gear 52; and on the arms of the spider are pivoted pawls 56, the rear ends of which are normally held against suitable stops 5? on the hack of the spider by a spring 58, while the points 59 of the pawls are adapted to engage with the cogs of the wheel in advance of the toothed segment The travel of the spider is restricted by the stops 60, carried by a bracket attached to the tambour frame, and adapted to engage with the arms and arrest the movement of the spider.

When the yieldable grip is open, as shown in Fig. 4, the spider 53 will be in the po' sition shown in Fig. 7 and the teeth of the segment El will be free of the teeth of the wheel If now the shaft 19 is revolved from right to left, the pawl 56. which is in Contact with the teeth of the wheel will immediately engage therewith, turning the spider and throwing the segment 54' into engagement with the gear 52, which will. carry the spider around until the toggle joint 34, is carried past its dead center. locking the yieldable grip in a closed position, coincidently with which the segment 5i will pass out of engagement with the gear 52 and the following pawl 56 will yieldably contact with the teeth of the gear 02. allowing that gear to continue to revolve without further effect upon the spider and its connections. But, as soon as the d rection of rotation of the gear 52 is reversed, the last mentioned pawl 56 will immediately engage with a tooth of the gear 52, throwing the segment 54 into engagement with the gear, unlocking and opening the yieldable grip and returning the spider to the position shown in Fig. 7.

This modification has the advantage of a positive connection between the tractive mechanism and the yieldable grip mechanism, insuring certainty of action, and avoiding the shock and following strain incident to the use of a slipping connection such as that afforded by the friction disk 27.

Having thus described my invention what I claim and desire to secure by Letters Patent of. the United States is:

1. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with multiple and locally yieldable fabric-pressing elements and a laterally acting tractor cooperating with a plurality of the fabric-pressing elements.

2. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with multiple automatically and locally yieldable fabricpressing elements and a laterally acting tractor cooperating with a plurality of the fabric-pressing elements.

In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with elements constituting a multiple, fabric-pressing device, which elements are severally adapted to yieldably engage against the same side of a fabric, and a cooperating lateral tractor engaging against the other side of the fabric.

4.111 an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric. each provided with a multiple automatic, fabric-pressing device, provided with elements which are severally adapted to vieldably engage against the same side of a fabric. and a coiiperating lateral tractor eng ging against the other side of the fabric.

5. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with a fabric engaging device embracing a plurality of independently yieldable elements. all adapted to simultaneously engage directly againstthe same side of a fabric, and a cooperating lateral tractor engaging against the other side of the fabric.

6.11] an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with a plurality of independently yieldable elements severally adapted to frictionally engage directly against the same side of a fabric and cooperating with a lateral tractor engaging against the other side of the fabric.

7. In an embroidering machine of the class mentioned the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with a plurality of independently movable elements severally adapted to engage against the same side of a fabric, and a laterally-acting cooperating element adapted to engage with the other side of the fabric.

8. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with a plurality of independently rotatable elements severally adapted to engage against the same side of a fabric, and a laterally acting coo'perating rotatable element adapted to engage with the other side of said fabric.

9. In an en'ibroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each comprising a plurality of independently yieldable and rotatable elements severally adapted to engage against one side of a fabric and a cooperating, rotatable, laterally tractive element adapted to engage with the other side of such fabric.

10. In an embroidering machine of the class mentioned, the combination with a tambour frame, of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with a laterally acting tractive fabric-engaging element and a multiple system of independently move able cooperating fabric engaging elements.

11. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each provided with a laterally'acting tractive element having a primarily-acting, frictional, gripping portion and a secondarily-acting, positive, gripping portion, and a multiple system of cooperat ing, frictional, fabric-gripping elements.

12. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism, adapted to engage the edge of the fabric, provided with a tractive element presenting successively tentative and positive engaging means, a plurality of cooperating fabricpressing elements and automatic means for disengaging the same from the fabric before the tractive element releases its positive engagement therewith.

13. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism provided with a tractive element having frictional and positive fabric-engaging means, cooperating engaging elements, and automatic means for causing the latter to engage the fabric coincidently with the effective frictional engagement of the tractive element therewith and to be disengaged from thefabric before the tractive element releases its positive engagement therewith.

14. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a rotary tractor, a cooperating grip and means for causing the initial effective movement in either direction of the tractor to change the lateral position of the grip relative thereto.

15. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a rotary tractor, a pivoted cooperating grip, a grip controller actuated by the initial movement of the tractor, and eX- tensible means projected or retrieved by said controller to open or close the cooperating grip.

16. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a rotary tractor provided with tentative and positive fabric engaging elements, a pivoted cooperating grip, a toggle joint interposed between the tractor and the grip, and means yieldably connected with the tractor for extending or contracting said toggle joint to open. or close the grip.

17. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms adapted to engage the opposite edges of the fabric, each provided with a laterally acting fabric tractor and a plurality of springpressed, cooperating grip elements for yieldably pressing the fabric against the tractor.

18. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each comprising a fabric tractor and L;

a plurality of independently yieldable elements provided with fabric engaging rollers for pressing the fabric against the tractor.

19. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanisms, adapted to engage the opposite edges of the fabric, each comprising a laterally acting fabric tractor and a cooperating, composite grip including a plurality of independently yieldable elements each provided with a terminal member adapted to travel with the fabric and to press it against the tractor.

20. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a tractor provided with a slippable fabric-engaging portion and a positive fabric-engaging portion, and a cooperating grip provided with a plurality of independently movable fabric-engaging elements.

21. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a laterally acting tractor adapted to slippably engage the fabric on one side, and a cooperating grip including a plurality of independently-yieldable units for pressing the fabric against the tractor.

22. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a tractor having primary and slippable and secondary and positive fabricengaging elements, and a cooperating grip having fabricpressing portions adapted to travel independently with those portions of the fabric with which they severally engage.

23. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a laterally acting tractor, and a grip cooperating therewith and having fabric-pressing portions adapted to travel independently with those portions of the fabric with which they severally come in contz' L.

2%. In an embroidering machine of the class mentioned, the combination with a tambour frame of means for evenly tensioning a portion of fabric, comprising a plurality of independently movable pressing elements and a laterally acting tractor cooperating with said pressing elements and adapted to slippably grip the fabric and successively stretch different parts thereof.

25. In an embroidering machine of the class mentioned, the combination with a tambour frame of fabric-engaging means comprising a plurality of independently movable pressing elements and a laterally-acting tractor cooperating therewith, said pressing means being adapted to slip locally against the adequately tensioned parts of the fabric.

In an embroidering machine of the 1 class HlOIltiUDOCl, the combination with a tamhour frame of tensioning mechanism comprising laterally-acting, unitary, tractive means, and cooperating means embracing multiplicity of units severally, independently adjustable relative to the tractive means, for progressively stretching different parts of a fabric to a desired tension, slippably holding it stretched by the movementof the tractive means, and for stretching the remaining parts to a uniform tension.

27. In an embroidering machine of the class mentioned, the combination with a tambour frame of tensioning mechanism comprising laterally-acting, unitary, tractive means, and cooperating means embracing a multiplicity of units severally, indcpend ently adj ustablc relative to the tractive means, for prij I essively stretching different parts of a fabric to desired tension and persistently maintaining such tension by the movement of the tractive means.

28. In an embroidering machine of the class mentioned, the combination with a tambour frame of tensioning mechanism comprising laterally-acting, unitary, tractive means, and cooperating means embracing a multiplicity of units severally, independently adjustable relative to the tractive means, for progressively stretching different parts of a fabric to a desired tension, slippably holding it stretched by the movement of the tractive means, for stretching the remaining pa res to a uniform tension and positively holding the tension when obtained.

29. In an embroidering machine of the class mentioned. the combination with a tambour frame o f lateral tension mechanism conipri ng a rota"; tractor, a toothed wheel trawling thereu. n, a pivoted cooperating grip and grip actuating means embracing gearing intermittently meshing with said toothed wheel.

30. In an cmbroidcring machin of the class mentionml, the combination With a tambour frame of lateral tension mechanism comprising a rotary tractor, a toothed wheel traveling therewith, a pivoted cooperating grip and grip actuating mechanism embracing gearing meshing with said wheel only during the opening and closing of the grip.

31. In an embroidering machine of the class mentioned, the combination with a tainhour frame of lateral tension mechanism comprising a rotary tractor, a toothed wheel traveling therewith, a pivoted cooperating grip and grip actuating mechanism embodying a toothed segment engaging with said toothed wheel during the opening and closing of the grip.

In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism compri ing a rotary tractor, a toothed wheel trinxehng therewith, a pivoted cooperating grip and grip actuating mechanism embodying a segn'icntal gear provided with pawls to positively engage said toothed wheel at the commencement of its movement in either direction.

33. In an embroidering machine of the class mentioned, the combination with a tan-'ibour frame of lateral tension mechanism comprising a rotary tractor, a toothed Wheel traveling therewith, a pivoted cooperating grip and grip actuating mechanism embodying a segmental gear provided with pawls to positively engage said toothed wheel at the commencement of its movement in either direction but not impeding said toothed wheel after the segmental gear has traveled past it.

34:. In an embroidering machine of the class mentioned, the combination with a tambour frame of means for supporting a fabric and for holding it taut in one direction, and means for tightening the fabric in another direction, comprising devices arranged to operate on opposite sides of the fabric, one thereof being provided with a tractor to draw forward the fabric and the other thereof being provided with a plurality of fabric pressing members which may travel independently of each other when severally engaging different portions of the fabric.

35. In an embroidering machine of the class mentioned, the combination with a tambour frame of means for supporting a fabric and for holding it taut in one direction, and means for tightening the fabric in another direction, comprising cooperating devices arranged to operate on opposite sides and to draw forward the fabric, one of said devices having a plurality of independent and resilient members adapted to press the fabric against the other of said devices.

36. In an embroidering machine of the class mentioned, the combination with a tambour frame of means for supporting a fabric and for holding it taut in one direction, a plurality of opposed means for ti htening the fabric in another direction, each comprising cooperating devices arranged to frictionally engage against opposite sides of the fabric, one of said devices embracing a frictional tractor and the other of said de vices including a plurality of fabric pressing members which may travel independently of each other when severally engaging different portions of the fabric, and positive means for holding the fabric when tightened by said cooperating devices.

37. In an embroidering machine of the class mentioned, the combination with a tambour frame of means for supporting a fabric and for tensioning it in one direction, and a plurality of opposed means for tensioning the fabric in another direction, each comprising coiiperating devices adapted to engage on opposite sides of the fabric to grasp it between them, one of said devices embodying a plurality of independently rotatable members and the other thereof embodying a rotatable member.

38. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a rotary tractor, a pivoted c0- operating grip and intermediate means for causing the tractor to close the grip at the commencement of its movement in one direction and to open it at the commencement of its movement in the other direction.

39. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism, comprising a rotary tractor, a pivoted cooperating grip and intermediate means for causing the tractor to close the grip only at the commencement of its movement in one direction and to open it only at the commencement of its movement in the other direction.

40. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism, comprising a rotary tractor, a grip governing element operating therewith, a 00- operating grip, and grip operating means embracing elements intermittently actuated by the grip governing element coincidently with the initial movement of the tractor in either direction.

41. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism comprising a rotary tractor, a grip governing element operating therewith, a cooperating grip, and grip operating means embracing elements intermittently actuated by the grip governing element coincidently with the initial movement of the tractor in either direction.

42. In an embroidering machine of the class mentioned, the combination with a tambour frame of lateral tension mechanism, comprising a rotary tractor, a gear element traveling therewith, a pivoted cooperating grip, and grip actuating means embracing gearing intermittently actuated by the gear element.

JOSEPH A. GROEBLI.

Witnesses:

A. H. KURsnEID, AGNES GERHAUSER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). C. 

